<!DOCTYPE html>
<html lang="zh-CN">

<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    h2 {
      color: red;
    }
  </style>
</head>

<body>

  <h2>456</h2>
  <div>用户名：<input type="text"></div>
  <div>密码：<input type="password"></div>
  <div>
    <button>登陆</button>
  </div>
</body>

</html>